Kenyan counterterrorism sources are looking at a Norwegian citizen of Somali descent as a possible suspect in the Westgate mall attack last month , the sources told CNN on Friday .

The Norwegian citizen is believed to have ties to Mohamed Abdikadir Mohamed , known as Ikrima , who is regarded as one of the most dangerous commanders in the Somali terror group Al-Shabaab .

Norwegian intelligence services are in Kenya investigating Ikrima and the Norwegian citizen , the Kenyan sources said , and have also spoken to the latter 's sister in Norway .

Norwegian authorities have not yet released the Norwegian citizen 's name .

Kenyan authorities suspect Ikrima of involvement with the Westgate mall attack .

Al-Shabaab claimed responsibility for the bloody four-day siege at the upscale mall in Nairobi , where at least 67 people died .

U.S. officials said Ikrima was the target of a raid earlier this month by U.S. Navy SEALs on an Al-Shabaab compound near the town of Baraawe in Somalia . It 's believed that he escaped after the U.S. troops came under heavy fire .

A Kenyan intelligence dossier seen by CNN alleges Ikrima 's involvement with Briton Samantha Lewthwaite , a terror suspect known as the `` White Widow , '' in a foiled Mombasa attack in 2011 with Jermaine Grant , a fellow British citizen currently held in Mombasa on terror charges .

Kenyan intelligence sources say that Ikrima , who speaks six languages and grew up in Kenya , is the main `` point person '' between al Qaeda in Somalia and al Qaeda in the Arabian Peninsula , and that he has helped pinpoint Kenyan targets .

Recruiting operatives in the West ?

Morten Storm , a former informant who has worked for several Western intelligence agencies , has told CNN that he developed a close relationship with an Al-Shabaab figure called Ikrima between 2008 and 2012 . He said he is confident that it 's the same person who was targeted by U.S. forces .

Inside story on an Al-Shabaab commander

Storm , who is Danish , described Ikrima as a Somali-Kenyan Al-Shabaab operative who had spent time in Norway . He said that Ikrima made clear to him via e-mail that he was ready to send recruits from the West back home from Somalia to launch attacks .

Norwegian journalist Bent Skjaerstad told CNN his sources have confirmed that Ikrima had indeed spent time in Norway and had tried to recruit for Al-Shabaab in Europe . Skjaerstad , who reports on security and terrorism for TV2 , said Ikrima had lived there between 2004 and 2008 . He had failed to gain asylum status but had been given Norwegian travel papers .

Skjaerstad told CNN that according to his sources , Ikrima had traveled to Somalia while living in Norway and had used about a dozen aliases .

Friends of Ikrima who knew him from his time growing up on the Nairobi suburb of Eastleigh told CNN he traveled to Norway in 2003 and grew increasingly radicalized there .

The sources , who had kept up with him over the years , said Ikrima traveled in 2007 to London , where they lost contact with him . In 2008 they heard that he was in Somalia , where he has been based since .

Arabic is among the six languages spoken by Ikrima , and he studied French for two years at the Alliance Francais in Nairobi , his friends say .

Al-Shabaab in Norway

The possible involvement of the Norwegian citizen in the Westgate mall attack has highlighted concerns about the widening reach of the Al-Shabaab group outside Somali borders .

Stig Hansen , a security expert based in Norway and author of the book `` Al-Shabaab in Somalia , '' told CNN that if the Norwegian suspect is who he believes him to be , he lived in a small town in Norway but had connections with a wider group , not all of Somali origin .

He came to Norway at age 8 or 9 and stayed for a couple of years , during which time he gained Norwegian citizenship , Hansen said . He later returned to Somalia .

Al-Shabaab became quite popular among some Somali community groups in Norway from 2007 to 2009 , Hansen said , `` because they were wrongly seen as some kind of national resistance group . ''

Observers noticed contradictions between what the group said in its English - and Arabic-language messaging , he said , which contributed to ignorance within the diaspora about its real nature .

`` But the terrorist attacks inside of Somalia made it easier for the wider ethnic Somali community to see that this was really a terrorist organization , and it distanced itself , '' he said , making it less popular now .

However , this development brought its own problems , Hansen said , and not just in Norway .

`` What you have to look out for , also in the United States and the United Kingdom and all these other Scandinavian countries , are these small , small networks that are in one sense detached also from the Somali community leaders -- radicalized groups of youths and radical preachers , sheikhs , that go traveling around the various countries to try to incite , '' he said . `` That 's what we have to watch these days . ''

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A Norwegian citizen of Somali descent is investigated in the Kenya mall attack

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Kenyan antiterror sources say he may have ties to a suspected Al-Shabaab commander

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Norwegian intelligence services are in Kenya investigating both men

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Norwegian authorities have not yet released the Norwegian citizen 's name